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7d98a1783f222964bcde7d56dab77b822706204dBob Halley - Copyright (C) 2004-2011 Internet Systems Consortium, Inc. ("ISC")
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence - Copyright (C) 2000-2003 Internet Software Consortium.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson - Permission to use, copy, modify, and/or distribute this software for any
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson - purpose with or without fee is hereby granted, provided that the above
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4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<p><span class="application">named</span> — Internet domain name server</p>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<div class="cmdsynopsis"><p><code class="command">named</code> [<code class="option">-4</code>] [<code class="option">-6</code>] [<code class="option">-c <em class="replaceable"><code>config-file</code></em></code>] [<code class="option">-d <em class="replaceable"><code>debug-level</code></em></code>] [<code class="option">-E <em class="replaceable"><code>engine-name</code></em></code>] [<code class="option">-f</code>] [<code class="option">-g</code>] [<code class="option">-m <em class="replaceable"><code>flag</code></em></code>] [<code class="option">-n <em class="replaceable"><code>#cpus</code></em></code>] [<code class="option">-p <em class="replaceable"><code>port</code></em></code>] [<code class="option">-s</code>] [<code class="option">-S <em class="replaceable"><code>#max-socks</code></em></code>] [<code class="option">-t <em class="replaceable"><code>directory</code></em></code>] [<code class="option">-u <em class="replaceable"><code>user</code></em></code>] [<code class="option">-v</code>] [<code class="option">-V</code>] [<code class="option">-x <em class="replaceable"><code>cache-file</code></em></code>]</p></div>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<a name="id2619370"></a><h2>DESCRIPTION</h2>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<p><span><strong class="command">named</strong></span>
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson is a Domain Name System (DNS) server,
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson part of the BIND 9 distribution from ISC. For more
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson information on the DNS, see RFCs 1033, 1034, and 1035.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson When invoked without arguments, <span><strong class="command">named</strong></span>
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson read the default configuration file
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <code class="filename">/etc/named.conf</code>, read any initial
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson data, and listen for queries.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson Use IPv4 only even if the host machine is capable of IPv6.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <code class="option">-4</code> and <code class="option">-6</code> are mutually
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson Use IPv6 only even if the host machine is capable of IPv4.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <code class="option">-4</code> and <code class="option">-6</code> are mutually
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson<dt><span class="term">-c <em class="replaceable"><code>config-file</code></em></span></dt>
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson Use <em class="replaceable"><code>config-file</code></em> as the
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson configuration file instead of the default,
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <code class="filename">/etc/named.conf</code>. To
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson ensure that reloading the configuration file continues
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff to work after the server has changed its working
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson directory due to to a possible
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson <code class="option">directory</code> option in the configuration
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson file, <em class="replaceable"><code>config-file</code></em> should be
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson an absolute pathname.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson<dt><span class="term">-d <em class="replaceable"><code>debug-level</code></em></span></dt>
f2fdfe7c42f3b10f3653f851ce5a0a90ee5ac1f9David Lawrence Set the daemon's debug level to <em class="replaceable"><code>debug-level</code></em>.
f2fdfe7c42f3b10f3653f851ce5a0a90ee5ac1f9David Lawrence Debugging traces from <span><strong class="command">named</strong></span> become
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson more verbose as the debug level increases.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson<dt><span class="term">-E <em class="replaceable"><code>engine-name</code></em></span></dt>
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson Use a crypto hardware (OpenSSL engine) for the crypto operations
553727079c69cacf56aaa8fd2722d04bfbbc8ce1David Lawrence it supports, for instance re-signing with private keys from
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson a secure key store. When compiled with PKCS#11 support
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <em class="replaceable"><code>engine-name</code></em>
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson defaults to pkcs11, the empty name resets it to no engine.
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson Run the server in the foreground (i.e. do not daemonize).
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson Run the server in the foreground and force all logging
94296c8d5b9c3c1ed13cf91c1f7b1d76d7fa0607David Lawrence<dt><span class="term">-m <em class="replaceable"><code>flag</code></em></span></dt>
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson Turn on memory usage debugging flags. Possible flags are
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <em class="replaceable"><code>usage</code></em>,
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <em class="replaceable"><code>trace</code></em>,
f2fdfe7c42f3b10f3653f851ce5a0a90ee5ac1f9David Lawrence <em class="replaceable"><code>record</code></em>,
f2fdfe7c42f3b10f3653f851ce5a0a90ee5ac1f9David Lawrence <em class="replaceable"><code>size</code></em>, and
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <em class="replaceable"><code>mctx</code></em>.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson These correspond to the ISC_MEM_DEBUGXXXX flags described in
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <code class="filename"><isc/mem.h></code>.
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson<dt><span class="term">-n <em class="replaceable"><code>#cpus</code></em></span></dt>
553727079c69cacf56aaa8fd2722d04bfbbc8ce1David Lawrence Create <em class="replaceable"><code>#cpus</code></em> worker threads
94296c8d5b9c3c1ed13cf91c1f7b1d76d7fa0607David Lawrence to take advantage of multiple CPUs. If not specified,
8803b0510877fd08044542edbb55e2be72fae36fAndreas Gustafsson <span><strong class="command">named</strong></span> will try to determine the
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson number of CPUs present and create one thread per CPU.
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson If it is unable to determine the number of CPUs, a
f4c0131a46ea183238027ef9c3400cc6079b8b85Andreas Gustafsson single worker thread will be created.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<dt><span class="term">-p <em class="replaceable"><code>port</code></em></span></dt>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Listen for queries on port <em class="replaceable"><code>port</code></em>. If not
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson specified, the default is port 53.
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson Write memory usage statistics to <code class="filename">stdout</code> on exit.
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence This option is mainly of interest to BIND 9 developers
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson and may be removed or changed in a future release.
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson<dt><span class="term">-S <em class="replaceable"><code>#max-socks</code></em></span></dt>
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson Allow <span><strong class="command">named</strong></span> to use up to
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson <em class="replaceable"><code>#max-socks</code></em> sockets.
581db30788a4920ba8558287a0dccf3c1a210c5aAndreas Gustafsson<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson This option should be unnecessary for the vast majority
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson The use of this option could even be harmful because the
b2c71d98dfc4dab5c6b8c8f39cf8fed3d899e94cAndreas Gustafsson specified value may exceed the limitation of the
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson underlying system API.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson It is therefore set only when the default configuration
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson causes exhaustion of file descriptors and the
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson operational environment is known to support the
3ddd814a97de1d152ba0913c592d6e6dc83d38a6Michael Graff specified number of sockets.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Note also that the actual maximum number is normally a little
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson fewer than the specified value because
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson <span><strong class="command">named</strong></span> reserves some file descriptors
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson for its internal use.
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence<dt><span class="term">-t <em class="replaceable"><code>directory</code></em></span></dt>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson to <em class="replaceable"><code>directory</code></em> after
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson processing the command line arguments, but before
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson reading the configuration file.
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
cf573ce6fb91d8d514425849c73cdbc2096d97e1Mark Andrews This option should be used in conjunction with the
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff <code class="option">-u</code> option, as chrooting a process
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson running as root doesn't enhance security on most
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson systems; the way <code class="function">chroot(2)</code> is
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson defined allows a process with root privileges to
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson escape a chroot jail.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<dt><span class="term">-u <em class="replaceable"><code>user</code></em></span></dt>
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence to <em class="replaceable"><code>user</code></em> after completing
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence privileged operations, such as creating sockets that
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff listen on privileged ports.
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence On Linux, <span><strong class="command">named</strong></span> uses the kernel's
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson capability mechanism to drop all root privileges
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson except the ability to <code class="function">bind(2)</code> to
3ddd814a97de1d152ba0913c592d6e6dc83d38a6Michael Graff privileged port and set process resource limits.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Unfortunately, this means that the <code class="option">-u</code>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson option only works when <span><strong class="command">named</strong></span> is
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson on kernel 2.2.18 or later, or kernel 2.3.99-pre3 or
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson later, since previous kernels did not allow privileges
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson to be retained after <code class="function">setuid(2)</code>.
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence Report the version number and exit.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Report the version number and build options, and exit.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<dt><span class="term">-x <em class="replaceable"><code>cache-file</code></em></span></dt>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Load data from <em class="replaceable"><code>cache-file</code></em> into the
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson cache of the default view.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson This option must not be used. It is only of interest
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence to BIND 9 developers and may be removed or changed in a
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence future release.
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence In routine operation, signals should not be used to control
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence the nameserver; <span><strong class="command">rndc</strong></span> should be used
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson Force a reload of the server.
cfefc47443d2035d13c827837e286f12c23e6eb4David Lawrence<dt><span class="term">SIGINT, SIGTERM</span></dt>
3ddd814a97de1d152ba0913c592d6e6dc83d38a6Michael Graff Shut down the server.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson The result of sending any other signals to the server is undefined.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson The <span><strong class="command">named</strong></span> configuration file is too complex
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson to describe in detail here. A complete description is provided
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff <em class="citetitle">BIND 9 Administrator Reference Manual</em>.
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff <span><strong class="command">named</strong></span> inherits the <code class="function">umask</code>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson (file creation mode mask) from the parent process. If files
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff created by <span><strong class="command">named</strong></span>, such as journal files,
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson need to have custom permissions, the <code class="function">umask</code>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson should be set explicitly in the script used to start the
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson <span><strong class="command">named</strong></span> process.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<dt><span class="term"><code class="filename">/etc/named.conf</code></span></dt>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson The default configuration file.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<dt><span class="term"><code class="filename">/var/run/named/named.pid</code></span></dt>
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson The default process-id file.
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff <span class="citerefentry"><span class="refentrytitle">named-checkconf</span>(8)</span>,
419590499823ce15b5d2ad4fe71eaf04bd5a86c0Michael Graff <span class="citerefentry"><span class="refentrytitle">named-checkzone</span>(8)</span>,
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson <span class="citerefentry"><span class="refentrytitle">rndc</span>(8)</span>,
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence <span class="citerefentry"><span class="refentrytitle">lwresd</span>(8)</span>,
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson <span class="citerefentry"><span class="refentrytitle">named.conf</span>(5)</span>,
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson <em class="citetitle">BIND 9 Administrator Reference Manual</em>.
4cd3d6df39927315e3fadc07a8da3788175f4195Andreas Gustafsson<p><span class="corpauthor">Internet Systems Consortium</span>
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